A typical image forming apparatus uses toner or ink to form images on paper. The toner or ink most commonly comes in four different colors—cyan, magenta, yellow, and black (CMYK). In a typical operation of an image forming apparatus, a print job is received, a color conversion process from the image color space (such as RGB) to the printing color space (such as CMYK) is performed, and an appropriate amount of each of the colors of toner or ink is applied to form an image on a page. However, using every single color of toner or ink in order to produce an image on a page may result in a poor quality and visual artifacts. For instance, printing a page consisting mostly of black or gray text against a white background using cyan, magenta, yellow, and black toner or ink may produce “color fringes” (sometimes referred to as “chromatic aberrations”) around the text, resulting in a fuzzy text printed onto the page.
In order to remedy the quality issues when printing with all colors of CMYK toner or ink, a color profile may be employed that specifies how color conversion is performed. The color profile is used to convert the document or image in a print job from its original color space (such as RGB) to a CMYK color space, which may then be employed by an image forming apparatus to use CMYK toner or ink to produce an image on a page. In the example of a document consisting mostly of black text against a white background, a text color profile that converts a document or image into CMYK color space maps RGB color pixels to CMYK pixel values and maps RGB black/gray pixels to K-only pixel values; in other words, pixels with color are mapped to full CMYK values, whereas pixels without color (black or gray) are mapped so that the CMY values are set to zero and only the K value remains. Employing a text color profile thus does not produce a black and white only document, but instead suppresses the use of cyan, magenta, and yellow toner or ink for any pixels that are black or neutral gray, thereby avoiding the color fringes while still printing a document in color. Thus, sending a printer both the image to be printed and a color profile may improve the quality of the image to be printed onto a page. Note that the color profile sent to an image forming apparatus is typically included as metadata along with the raster data, and has been predetermined by a computer, for example.
The image forming apparatus may select the color profile used for a respective print job based on metadata contained within the print job information received by the image forming apparatus (from a personal computer, for example). This metadata may be configured in a variety of different ways for different printing devices. However, as the types of computing devices sending the data to image forming apparatuses and print job data format standards become increasingly diverse, it becomes more difficult to have a particular computing device send compatible data to a particular image forming apparatus. In other words, in order to execute a print job on a specific image forming apparatus, a computing device must be aware of the print job data format compatible with that specific image forming apparatus.
In order to remedy the compatibility issues that arise from these different printing standards and increasing diversity of computing devices, the metadata may be removed entirely and the raster data by itself may be sent to an image forming apparatus. This provides the advantage of improved compatibility in printing documents from a variety of computing devices to a variety of image forming apparatuses; however, it removes the ability to send over the document type containing a color profile that was previously embedded in the metadata.
In current implementations, an image forming apparatus may employ a default color profile that may not be appropriate for printing a respective print job. For example, the default color profile may be a photo color profile, even though the document contains mostly black or gray text, thus causing the image forming apparatus to unnecessarily print the text using colors other than black, which may result in “color fringes” and other visual artifacts to be formed on the printed page.